Medical Information

• What is Influenza?
• What is Pandemic Influenza?
• Prevention Strategies
• Vaccines
• Antiviral Drugs

Prevention Strategies

General Hygiene and Infection Control

Everyone should be aware of the basic hygiene techniques and principles for protection against respiratory pathogens. This applies both in the workforce and outside work, and is relevant to the whole community.

The principles of infection control and the management of infectious cases of pandemic influenza and their contacts is determined by the mode of transmission, the incubation period and the infectious period.

Transmission of Influenza is by:

• Droplet (respiratory secretions) transmission is common among close (within one metre) contacts.
• Contact (respiratory secretions) transmission may occur through hand-to-mouth or hand-to-eye transmission after touching an influenza virus-contaminated object or surface. Hand-to-hand transmission is possible.
• Airborne transmission predominates among crowded populations in enclosed spaces.

The incubation period for human influenza viruses is two to three days, with a range of one to seven days. A small proportion of patients may be infectious from just before symptoms appear. The infectious period is usually from the onset of symptoms to seven days since resolution of fever (in those over 12 years of age); and 21 days since onset of illness (in those under 12).

Therefore the mainstay of avoiding infection is in the avoidance of being exposed to droplets (coughs and sneezes of an infected person), dirty hands and exposed surfaces that have droplets on them.

General Advice for prevention of influenza transmission

This is relevant to everybody, including people who have symptoms.

Cleaning and disinfection

Cleaning and disinfection is also important for surfaces that can be coughed or sneezed on, or handled by the public.

The H5N1 influenza virus is inactivated by alcohol and by chlorine. Cleaning of environmental surfaces with a neutral detergent followed by a disinfectant solution is recommended.

Masks and handwash

P2 (N95) masks are expected to minimise air-borne and droplet transmission of respiratory secretions from an infectious case to the attending person. If used, they should be properly fit tested. They are potentially uncomfortable to wear, so a proper fit is very important. Staff who may have to have exposure to the public during phase 5 and 6 of a pandemic should wear a P2 (N95) mask.

Surgical masks are not as protective but are expected to minimise droplet transmission of respiratory secretions from an infectious case to other close contacts. Unless it needs to be removed for examination purposes, the infectious case should wear a surgical mask to minimise exhalation of respiratory secretions when other people are within 1 metre or are in the same room. People with coughs and sneezes in public areas should be encouraged to wear a surgical mask in phase 5 and 6 of a pandemic.

Handwashing is an important preventive measure for respiratory disease, and soap and water and proper drying is recommended. Antibacterial hand cleansing gel is also useful, especially where ordinary washing is not available.

General advice on preventing Avian influenza

People in areas where avian influenza is active amongst birds, should take precautions to avoid transmission of avian influenza. The following strategies are important:

• Avoid all direct contact with poultry (chickens, ducks, geese) and wild birds, even if the animals appear to be well. Avoid farms and live-animal markets.
• Avoid touching surfaces contaminated with poultry faeces or secretions, and avoid contact with fertilizers made from poultry faeces.
• Avoid swimming in water bodies where wild and domestic birds gather.
• Do not eat undercooked poultry meat/organs/blood. The cooking temperature for poultry meat should reach 70oC. Do not place cooked meat on the same surface it was on before it was cooked.
• Do not eat undercooked eggs. Egg yolks should not be runny or liquid, and raw or soft boiled eggs should not be used in foods that will not be cooked. Wash egg shells in soapy water before handling and cooking, and wash your hands afterwards.
• Hand hygiene with frequent hand washing using soap and water (or alcohol hand rubs) is good practice for prevention of many infectious diseases, including avian influenza. Wash hands after handling all raw or cooked foods.
• If you think you have been exposed to avian influenza, monitor your health for 10 days. Consult a health care provider if you become ill with fever and respiratory symptoms within 10 days of returning from an affected area.

Selective Social Distancing

During a pandemic of influenza, measures to increase the separation of people (social distance), and restrict mass gatherings may be instituted or recommended. These measures, which include closure of schools and restricting gatherings such as concerts or sports events, are intended to prevent transmission of influenza between people. In the setting of influenza, as people may be infectious before the onset of symptoms, measures that reduce contact between people regardless of symptom status may be particularly effective.

WHO has recommended that authorities consider all measures to prevent spread of disease depending upon the characteristics of the particular pandemic strain, and the feasibility of the interventions, given their significant social and economic implications. So exactly what functions might get closed is not known at this time. It is possible that some public transport and non-essential business will be recommended to close.

It may be that businesses that include gatherings of people in the course of their work, eg markets, entertainment, sport, public transport, etc, will be required to close those operations.

Back To Top